NASA hopes to revive powerless Phoenix Mars Lander

The Phoenix Mars Lander was last heard from Nov. 2, 2008, when a fierce dust storm starved the spacecraft of solar power and cut off its communication with Earth.

With the long, harsh Martian winter closing in, NASA decided to wait until temperatures warmed up to try to contact the lander again.

Over a year later, spring is finally under way on Mars. Later this month, scientists will try to bring the lander back to life.

If NASA is successful, the craft may be able to generate more findings about the Red Planet. Already, it has proved the planet contains water, a key ingredient in supporting life.

But reviving the lander, which launched in 2007 with the goal of studying the history of water and the possible habitability of Mars, is a long shot at best.

The craft's solar panels may have broken under a sheet of carbon-dioxide frost. Without solar power, the lander would have no way to charge its batteries and switch on its electronics. Extremely low temperatures also may have cracked and damaged the electronic systems.

"I'd like to think there's a high probability (of reviving the lander), but there isn't," said Peter Smith, the mission's lead scientist and a University of Arizona professor. "The winters are extremely cold and long, and we never tested the spacecraft under those conditions. Usually, when you go outside your test limits, bad things happen."

A rare mission

Missions to the Mars surface are rare, happening about once every five years and costing hundreds of millions of dollars. Therefore, NASA has a vested interest in getting the spacecraft to function again.

The next Mars mission, the Mars Science Laboratory, isn't planned to launch until fall 2011 and will take a year to reach the planet.

The craft landed on May 25, 2008, in the northern polar-region circle and spent five months analyzing soil samples, recording temperatures and taking pictures. The lander was always designed to be a short mission, lasting only a few months.

"It's rather tough living up north in the arctic circle," Barry Goldstein, NASA's Phoenix Project manager, said during a 2008 news conference. During the Martian summer, daytime temperatures often get no higher than 22 degrees below zero.

But if NASA is successful in reviving the lander, it's possible the science instruments would still function and could resume work.

Equipment aboard the lander includes a robotic arm for scooping and digging up soil samples, microscopes, and a tiny oven that is capable of heating up soil samples and analyzing the contents of the gases.

Scientists would still like to determine whether the Martian soil contains organic compounds, such as carbon and hydrogen, which are the building blocks of life.

Making contact

The first step in the process is determining whether the lander is even reachable.

NASA chose mid-January to start communicating because it will be spring on Mars. Martian seasons don't correspond to the Earth's. They are twice as long because Mars takes longer to orbit the sun. This is the first opportunity for NASA to reach the spacecraft when conditions are most favorable.

As the sun climbs higher in the sky and the days become longer, the solar panels, if they still function, would start powering up the electronics.

Eventually, the panels would generate enough power for the craft to stay awake for long periods.

NASA plans to send signals to the craft using an orbiter that communicates through ultra-high frequency radio signals.

The messages will ask the spacecraft, "Are you awake?"

If the craft is functioning, it will send a signal back.

Landmark trip

However, even if NASA fails to reach the lander, the $428 million mission would still be viewed as a success.

The craft was the first to confirm the long-held theory that water, in the form of ice, exists on Mars.

It also found nutrients in the soil that are necessary to support life, including minerals such as sodium, magnesium and chloride as well as a salt called perchlorate.

Microbes on Earth use perchlorate as an energy source.

Cameras aboard the lander also captured more than 25,000 pictures, showing jagged rocks scattered over a rust-colored landscape. UA received international attention for its leading role in the science mission.

Smith would love to do more research, although there are other hurdles.

"Frankly, we have no budget left," he said. "We'd have to ask for money to operate the spacecraft. We'd have to build a science case for even doing anything."

It's likely NASA's orbiter will try to reach the lander multiple times over several months.

"We will certainly try," Smith said. "If there's any hint of something alive, we will try much harder. Even one beep (back) is all we'd need to get everybody excited."